PLATTSBURGH, N.Y. — A prison guard charged in connection with the escape of two killers admitted providing them with tools, paint, frozen hamburger and access to a catwalk electrical box, but claims he never knew they planned to bust out, authorities say.

As the search for the convicts entered its 20th day Thursday, Gene Palmer was released on $25,000 bail after his arrest on charges of promoting prison contraband, tampering with evidence and official misconduct.

Palmer, 57, became the second Clinton Correctional Facility employee to be charged since Richard Matt and David Sweat used power tools to cut their way out of the maximum-security prison in far northern New York on June 6.

But in contrast to the allegations against Mitchell, Palmer said he was an unwitting helper.

“I did not realize at the time that the assistance provided to Matt or Sweat made their escape easier,” he told authorities in a signed statement.

District Attorney Andrew Wylie said that based on Palmer’s statements and a polygraph test, investigators have no reason to believe he was knowingly involved in the escape.

In the statement, Palmer admitted providing Matt with paint and paintbrushes. On four occasions over eight months, he supplied Sweat with needle-nose pliers and a screwdriver. He said he gave Sweat access to the catwalk later used in the escape to change the wiring on electrical boxes as “a favor” to make it easier for them to cook in their cells.

And a week before the escape, he delivered to Matt a pound of frozen ground beef in a package left by Mitchell.

“Matt provided me with elaborate paintings and information on the illegal acts that inmates were committing within the facility,” Palmer told authorities. “In turn, I provided him with benefits such as paint, paintbrushes, movement of inmates, hamburger meat, altering of electrical boxes in the catwalk areas.”

Wylie said Mitchell told investigators she smuggled hacksaw blades, a screwdriver and other tools into the prison by hiding them in the frozen meat.

She then put the meat in a refrigerator in the tailor shop, and Palmer took the meat to Sweat and Matt, who were housed in a section where inmates are allowed to cook their meals, according to the district attorney.

Wylie said Thursday that investigators have no proof Palmer knew hacksaw blades were embedded in the meat.

After the escape, Palmer burned and buried the inmate paintings, according to court documents.

Palmer, who has been suspended, will plead not guilty, according to his lawyer. The misconduct charge relates to receiving the inmate-made paintings in exchange for the contraband pliers and screwdriver. The tampering charges stem from the destruction and concealment of the paintings.

Authorities say the inmates cut through the steel wall at the back of their cells, crawled down a catwalk, broke through a brick wall, cut their way into and out of a steam pipe and then emerged from a manhole outside the prison.

Sweat, 35, was serving a life sentence without parole in the killing of a sheriff’s deputy. Matt, who turned 49 on Thursday, was doing 25 years to life in the kidnapping, torture and hacksaw dismemberment of his former boss.

Palmer had worked at the prison in Dannemora for more than 27 years and had a base salary of $72,644. He had known Sweat and Matt for at least five years.

In a 2000 interview with upstate New York’s North Country Public Radio, Palmer portrayed the job as highly stressful.

“With the money that they pay you,” he said, “you’ll go bald, you’ll have high blood pressure, you’ll become an alcoholic, you’ll divorce, and then you’ll kill yourself.”

Away from his day job, Palmer was a bandanna-wearing rocker, singing and playing guitar and keyboard in Just Us, a band that covered such baby-boomer songs as Johnny Cash’s “Folsom Prison Blues” and Bon Jovi’s “Runaway.”

“He’s a great guy. Always treated everybody fairly here,” said Christopher Brothers, manager of Fuzzy Ducks bar in Morrisonville, where Just Us has played. “I don’t want to jump to conclusions. It seems like he may have done bad things, but I hope people take into consideration he also gave 28 years of his life to that prison.”

About 1,100 federal, state and local law enforcement officers took part in Thursday’s search, which focused on a 75-square-mile area dominated by heavy woods.